ABS Rings Rear Audi A4 1997

Hello!

A friend's son wanted to "quickly" replace his rear brake calipers today.
Audi A4, manufactured in 1997.

He then also brought along brake discs and brake pads. He ordered them online, just like young people do these days.

These are brake discs like the ones from the past, where the wheel bearings are pressed in. (I never thought they would still be installed this way on an A4.)
Well, of course, he didn't have any new wheel bearings, so I called his father and told him to go to the next auto parts store to buy some more wheel bearings.
It worked out, and while I was working on it, it occurred to me that there are still the ABS sensor rings there.
So, I called the dealer to make sure he includes the bearing rings with the sale.

Everything worked out. He then brought the wheel bearings and ABS sensors, and we had already disassembled the brake quite a bit.

The original donor rings were made of sheet metal, while the new ones are solid steel.

"Okay, I thought. It looks sturdy, and it fits. The number of teeth is also correct."
I pressed the wheel bearings in, and I also installed the sensor rings.

Fortunately, I checked again to see what the distance was between the ABS sensor ring and the sensor.
Too big.
Maybe 4 mm.
This isn't going to work.

I managed to get the rings back on gently, hopefully without bending them.

I somehow need to get them in the correct position and perfectly round.
This will require patience...

How do you do that properly?
Can someone please tell me the distance to the sensor?

Basically, I can get along quite well with a system of knowledge based on intuition.

What kind of ridiculous construction is this?

It seems to me that soon it will be necessary to press the encoder rings into the exact correct position using a special machine or device, which may be the case in mass production.
But as a craftsman, you're really good.

Hi Steffen,
Without a guide, you're completely lost here.
Could you tell me the type of engine, as well as the engine code (MKB) and gearbox code (GKB)? And could you provide some photos?
Maybe then you'll be able to make progress.
hg
Herbert.

Hello Steffen,

Audi uses a simple sleeve to press the rotor onto the wheel hub.

Tool VW 32-119.

After adjusting the wheel bearing preload (the pressure plate must remain movable laterally), the central nut is tightened in two steps.

1. 115 Nm

2. Rotation angle of 180 degrees.


Best regards,

Michael.

Hello!

I'd like to share how things turned out:

So, the car is finally put back together and working properly again.

I don't have any vehicle data right now, and it's not necessary anymore.
That was a 1997 model, gasoline engine.

In the picture, you can see the black sensor ring for the ABS system. It was something that could have been purchased pre-assembled, but it wasn't.

This brake-wheel bearing assembly is constructed similarly to those found in Golf 1, Golf 2, and Golf 3 models, using the classic tapered roller bearings. The outer, smaller bearing was larger than it was in the earlier Golf 2.
The oil seal has an additional dust lip on the outside, which makes it more difficult to install.
I adjusted the wheel bearing exactly as I'm used to from previous experiences with Golf 2 models, etc.

Okay, I then carefully adjusted the toothed rings into the correct position, achieving a runout of less than 0.1 mm and a distance of 0.5 mm from the ABS sensor.

It would have been correct to use a flat plate and turn an aluminum ring that is approximately 10 mm high, but I didn't have suitable material.
I could have used that to press it in properly. But it's also difficult to measure accurately beforehand whether it's exactly 10 mm or 9.5 mm.
Since the oil seal was already in place, and I didn't have a new one, it simply wouldn't fit. It would have interfered with the installation.
So, it's quite a flimsy construction.

As a small addition:
When installing new brake calipers, it's necessary to bleed the brakes.
I then said, well, so far, the brake fluid reservoir has only burst once, and I'm going to reduce the pressure to 0.9 bar. It's because of the old car...

And as I said, I turn the valve on the bleeder device, and of course, a jet of brake fluid immediately shoots out from the container, through the ventilation slots in the hood, and all over the roof.
Of course, the sunroof was also open.

In anderen Foren gibt es ein "schwarzes Museum, Pleiten. "Bad luck and mishaps."
That's where this post would fit in.

So, we had to bleed the brakes the old-fashioned way, using the brake pedal.
It worked, though. I told him three times to please not press the brake pedal all the way down, just to see if he would do it.

Hi Steffen,

Does the "stub" of the wheel bearing housing that contacts the brake disc have a flange that, after the rotor is pressed on, is flush with the inner edge of the rotor (as visible in your picture)? This would explain the simple tool 32-119. You press on until the tool reaches its stop.

Otherwise, there would either have to be a measuring device or a stop for the rotor.

Besides, since I don't have a press, I always run a threaded rod through the center whenever possible, and use appropriate plates or rings to secure it.

hg
Herbert.

As I said, the wheel studs have the original sensor rings, which are simply knocked out by drilling through the holes.

The distance to the sensor is adjusted using the sensor itself, which is mounted in a floating manner within a sleeve. You adjust it by moving it all the way in and then pulling it back a tiny bit.

To install the sensor ring, I use an outer ring from a wheel bearing that I've taken from my collection of spare parts. I place a flat piece of iron on top, align it carefully, and then use strong blows to press the sensor ring into place. Of course, the old sensor ring is cleaned of any rust beforehand.

Furthermore, there are different rear wheel bearing variants for the A4 B5, and a change occurs around 1997, so it's important to pay attention to that as well.

Additions, because yesterday I just quickly posted it to the forum.